Building Zones W2/W3 & the Zoning Plan Explained
The building zone determines whether and how densely you may build on a parcel. Residential zones such as W2 or W3 cap, among other things, the number of storeys and the plot ratio; the municipal zoning plan assigns each parcel its zone. This page explains what the zone label means and what to check in the zoning plan before you buy.
This page explains publicly accessible registers and does not constitute tax, legal, construction, or financial advice. Consult a qualified professional for legal or tax questions.
Whether a parcel suits your plans depends first on its building zone. It governs use, the number of storeys, and density — before questions of architecture or financing even become relevant.
The building zone is part of the municipal land-use plan. It divides the municipal territory into zones — residential, commercial, agricultural, and protected — and sets, for each, what may be built and how it may be used. Which zone applies to a given parcel is shown in the zoning plan; the cantonal zoning plans are also viewable on geo.admin.ch.
Source: Federal geodata (geo.admin.ch)
In a residential zone the digit gives the maximum number of full storeys: W2 allows two-storey, W3 three-storey residential buildings. The exact rules on height, boundary distance, and plot ratio are not in the code but in the municipality's building and zoning regulations — the W2/W3 label is defined differently from canton to canton and municipality to municipality.
Source: Land-use planning, Canton of Zurich (zh.ch) · Glossary: plot ratio
The permitted building volume follows from the zone's plot ratio (Ausnützungsziffer) or floor-area ratio, not from the zone digit alone. It relates the chargeable floor area to the parcel area. Two equally sized W3 parcels can therefore permit different building volumes.
Source: Spatial development ARE (are.admin.ch) · Glossary: plot ratio
The zoning plan shows the base land use, but not every restriction. Special-use plans, design plans, building lines, or heritage protection can apply on top and further limit buildability. For a binding answer on a concrete project, the municipal building authority is responsible.
Every fact in an alpflo report carries exactly one of these states — so you can see at a glance what's documented and what isn't.
Confirmed in an official Swiss register. Direct source.
Register queried; nothing on this parcel. The absence is documented.
Derived from a model or an API: real, but not directly from the register. Please verify.
Hit an edge case. Stated honestly at the boundary, never silently discarded.
What does W2 or W3 mean?
The digit gives the maximum number of full storeys in a residential zone: W2 for two-storey, W3 for three-storey residential buildings. The exact dimensions are set by the municipal building and zoning regulations.
Where do I find a parcel's building zone?
In the municipal zoning plan. Zoning plans are available from the municipality and as geodata on geo.admin.ch; a binding answer is given by the municipal building authority.
Does the building zone tell me how large I can build?
Only partly. The zone digit gives the number of storeys, but the permitted volume follows from the zone's plot ratio or floor-area ratio combined with municipal rules.
Can the zone assignment change?
Yes. Municipalities periodically revise their land-use planning. A planned zone change can raise or restrict buildability — check for ongoing revisions with the municipality.
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